Jack



Feb. 8, 1938.

C. J. SMITH JACK Filed Dec. 5, 1935 Patented Fes. a 193s VnUNiTED STATES PATENT OFFICE -s,1o1,111 A v JACK Charles J. Smith, Dayton, Ohio, assigner to The Dayton Malleahie Iron Company, Dayton, Ohio, a ooml'ation of Ohio Application December `4i Claims.

' This invention relates to jacks, and more particularly to jacks adapted for engagement with the bumper or other portions of an automobile `or the like.

One-of the principal objects of the invention is theprovision of a reliable yet inexpensive jack Vthat is quickly adjustable for use within a wide range of lifting positions and that, although compact; affords an extended range of lifting travel.

Another object of the invention is the provision of such a jack incorporating a loadr supporting vmember that is slidably adjustable with respect tothe lifting structure and that is arranged to frictionally grip the lifting structure in any desired position upon application of a load thereto. "A further object of the invention is the provision of asimple and `compact jack incorporatinga lifting screw and a telescopically related sleeve in threaded engagement; the sleeve serving as a means of adjustably receiving the load supporting device oi' the jack, as a means of increasing the effective length of the lifting screw,

Vvand as, an enclosure for ,the screw in the co lapsed position of the jack.

Other objects and advantages of the invention will be apparent from the following de- I scription. the accompanying drawing, and the appended claims. v

In thel drawing which illustrates a preferred embodiment of the invention,-

Fig. 1 is a vertical sectional view of a jack constructed in accordance with this invention; i f Fig. 2 is a fragmentary elevational view lookving toward the lower Vend of the lifting screw:

' Fig. 3 is a plan view of the load supporting member;

Fig. 4 is a sectional view as indicated by the line 4-4 of Fig. 3; and A Fig.` 5 is a fragmentary vertical sectional view as indicated by the llneB--B of Fig. 1. The drawing, in which like. characters of reference designate like parts throughout the several views thereof, illustrates a jack which is particularly applicable for use for attachment to the frame uportion of an automobile such, for example, as the bumper bar orlike fitting, in 'y order 4to elevate the automobile an amount suilicient toenable a tire to be changed. Jacks 'of this character .are required to have an extended lift because of the yielding spring connection between the automobile wheel and the point of application of the jack and becauseof the general use of large section tires.' For these reasons the'iaclrmust lift a considerable distance before 8, 1935, Serial N0. 55,889

the wheel will clear the around. `A jack, to be satisfactory for such service must have a wide range of lifting positions and an extended range of lifting travel as well. In the jack of this invention these qualifications are incorporawd in a structure of compact form.

As shown, the jack comprises a base structure l0 upon which is rotatably mounted an upstanding screw shaft I2 of which the major portion is threaded as indicated at il. 'I'he base structure I0 comprises complementary housing p0rtions i5 and I6 which, as shown, have verticalabutting faces and are joined by rivets or bolts as indicated at i8. I'he assembled portions Il and I8 vprovide a hollow housing for support and guidance of the rotatable screw i2 and serve additionally as an enclosure for driving mechanism I8 by which the screw is rotated.

The lower portion of the screw I2, below the .threaded portion I3, is shown as having an annular 4 groove 20 formed therein. Below this groove the screw shaft is reduced to form an end portion 2| which is of non-circular contour and provides for driving engagement of the driving means by which the screw is rotated. The extreme lower end of the screw is formed as a convexface as indicated at 22 and is received within the axial depression 2l of a member 24 that projects upwardly from and is attached to the ground engaging part 25 of the base structure. As shown. the member 24 serves as an upstanding projection within the base housing .and is'l formed with a circular peripheral face. 21 for support of the screw driving mechanism. The member 24 is held in place through provision of an integral depending lug 28 that is flared outwardly Aat the lower end as indicated at 2l,

and which is closely received within aligned openings l0 provided at the Junction of the assembled housing portions.

In addition to the support afforded the screw byengagement with the base projection, the screw is additionally guided by the supstanding portions of the base housing parts as indicated at 32. As shown, the housing portions 32 nare outwardly and afford suilicient clearance with respect to the screw that it may have a slightl angular movement to accommodate a base positioning such as would occur when resting upon uneven or inclined surfaces.

Means are preferably provided whereby the screw and base structure are held in interengaged relationship although such means may be omitted if it is desired to provide forl convenient separation of the base portion from the 55 screw. As shown, the housing portions .33, at a point below the upper ends thereof, have inwardly projecting lugs 33 that are adapted to The driving mechanism i3 which serves to rotate the screw I2 and impart lifting movement to the jack comprises a gear 3l having an opening 36 toward one end of the hub which conforms in contour to 4the screw projection 2i and Vis adapted for loose driving engagement therewith', the interflt of these parts .being such that the screw may move angularly within the clearance afforded at the opening of the housing portions 32.- The lower portion of the hub of the gear 35 has an axial opening-31 which is a running ilt on the periphery of the upstanding member 24. The rotatable gear 35 has meshing engagement with a pinion 38 which is formed on the inner end of a rotatable sleeve 39 that is Journalled in the housing portions'. The upper end of the sleeve 39 is suitably socketed as indicatedat 40 for the reception of a crank handle or the like for operating the driving device.

The lifting action of the jack obtains through the medium of a' sleeve 42 which is of a length somewhat shorter than the screw but commensuratewith its threaded portion, andv which has threaded engagement therewith. As shown, the sleeve 42 is constructed of a tubular portion 43 which, -at its lower end, has amxed thereto a collar 44 comprising a threaded portion 45 that engages the screw and an upper sleeve like part 46 which telescopically receives the sleeve l2 and erally staggered pins or ngers 53 project.

'is suitably 'maintained in driving relationship member is of a diameter sumciently large that when held so that the axes of the ring and the sleeve coincide the supporting member may freely slide to any position upon the sleeve 42. The ring and sleeve diameters are so coordinated to permit inclination of the ring-like portion to an engagement with vthe sleeve such that a downwardly acting load at the lcadengasing Pins will cause the load supporting member to frictionally grip the sleeve and to be maintained thereon in fixed engagement. As shown, this gripping engagement obtains through contact with the sleeve ofl a ring face 51 which is preferably somewhat less in width than the thickness of the ring-like part 5l. It is to be noted that the axes of the staggered pins 53 are parallel and are inclined with respect to the axis of the ring portion 5l; the relationship being such that with the load supporting member in holding position on the sleeve the pin axes and sleeve axis are substantially parallel and upright.

vAlthough suitable gripping engagement may obtain by frictional contact of the ring face with a rather smooth' sleeve surface, the gripping enaioaviv y sagement is preferably made more positive by providing a roughened surface on the sleeve as through provision of a shallow spiral thread thereon, or by knurling the surface, as indicated at 58. In order to prevent accidental displacement of the load supporting member in the interval that the jack is being prepared for application to an object, suitable detent means may be provided to yieidingly hold the member 50 in desired position upon the sleeve. As shown, one side of the ring 5l is drilled as indicated at 30 to receive a spring 6I and ball 82 which function. as a frictional detent having sumcient holding force to yieldingly maintain the load supporting member in a desired position. Upon assembly of the spring and ball the open end of the drilled hole may be peened over an amount sumcient to prevent removal of the detent parts.

A plug cap 63 serves as a closure for the upperv end of the sleeve 42. If desired, the cap may have a diameter somewhat larger than shown to serve as-a convenient means for rotating the sleeve by hand upon the screw i2. y

It is thought that it will now 'be readily. apparent that a jack constructed in accordance with the present invention will afford a range-of travel such as is required of jacks of that character which are attachable to the frame portion or bumper bar of an automobile. It is further pointed out that this desirable result is obtained in a jack having a collapsed height considerably less than the extreme limit of lifting that may be obtained, in that the screw length is considerably less than the overall length with the sleeve extended and with the load supporting member positioned adjacent the upper end of the screw.

A wide range of load supporting positions are e afforded and a desired lifting position is readily i obtained' bymerely sliding the load supporting member along the sleeve to adesired location. Application of a load at any position of the load supporting member securely locks the member to the sleeve so that lifting movement may occur at any point withinv the length of the sleeve. y, addition to providing a compact structure in the telescoped position of the sleeve further advantages obtain in that the screw threads may be enclosed by the sleeve tov thus prevent damage .thereto and to permit the retention of lubricant thereon. Moreover the weight of the jack is cornparativelyv small, as the housing is very short and of small size.

While the form of apparatus herein described constitutes a preferred embodiment of the invention, it is to be understood that the invention -is not limited to this precise form of apparatus, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is: 1. A jack of the character described comprising a base, an upstanding threaded screw rotatably supported in said base and having a compat-- screw and provided above the top ofjsaid base throughout substantially the entire lifting range of said s1eeve,"said sleeve having a length commensurate with that of the screw and adapted when fully engaged therewith to substantially enclose said screw, load supporting meanskon the sleeve for engagement with an object'to be lifted, said load4 supporting means comprising a ring-like member rockable on the sleeve from a position in which the ring and sleeve axes coincide and in which the ring is slidable thereon to an inclined position in which the ring frictionally grips the sleeve and is xedly held thereto by the load.

2. In a Jack, a vertically movable member. means for. moving said member vertically, load supporting means movable on said member for engagement with an object to be lifted comprising a plurality of laterally staggered lupstanding conical ngers adapted to simultaneously engage spaced points on opposite sides of the bottom edge of an object in wedging contacttherewith.

3. A jack of the character described comprising a base, an upstanding threaded screw rotatably supported in said base. a sleeve telescopically related to and having threaded engagement with said upstanding screw, saldsleeve having a length commensurate with that of the screw and adapted when fully engaged therewith to substantially enclose said screw, load supporting means on the sleeve for engagement with an object to be lifted,

said load supporting means comprising a ring.

like member rockable on the sleeve from a position in which the ring is freely slidable thereon to an inclined position in which the ring trictionally grips the sleeve, said ring having a lateral pro- Jectlon thereon with upstanding iingers for en- 5 gagement with an object to be lifted. the axes of the fingers being parallel and inclined with respect to the ring axis, and means for rotating. the screw.

4. A jack o1' the character described comprising 10 an upstanding rotatable lifting screw having an annular groove adjacent the lower end thereof,

a housing comprising a ground engaging base having a projection for axial support of the lifting screw, said housing having an opening in the 15 upper portion vertically aligned with said projection for loose reception of the screw, rotatable driving means for the screw journalled on the base projection and operatively engaging the screw, and means on the housing interiittlng the 20 screw annular groove to maintain the housing and screw in assembly.

CHARLES J. SMITH. 

